ADM239LAR - 5V RS-232 Interface with DC-DC | Analog Devices
MPN: ADM239LAR ✓ Hoạt độngADM239LAR Tóm tắt
An RS-232 transceiver is an interface IC that converts logic-level digital signals into differential, bipolar RS-232 signals and converts received RS-232 signals back into CMOS logic levels. The RS-232 transceiver belongs to the serial-interface hierarchy, which includes interface ICs, line drivers and receivers, communication transceivers, and broader data-communication semiconductors. It is designed for equipment-to-equipment communication over cables where voltage levels exceed ordinary CMOS input and output ranges.
The ADM239LAR's principal advantages include operation from one 5 V supply, compliance with EIA-232-E and V.28 specifications, a maximum data rate of 120 kB/s, and an integrated DC-DC converter that generates the elevated RS-232 output voltage. Its 9 V output swing provides useful noise margin over the approximately 2 V RS-232 transition region. Low-power shutdown reduces consumption when the interface is not required, while the receiver remains active during shutdown.
The integrated charge-pump circuit develops the bipolar transmitter voltage required by RS-232 from the single 5 V supply. The manufacturer datasheet specifies small 1 μF capacitors for the charge-pump circuit. Three transmitters provide enough channels for common control, status, and data paths, while five receivers allow the opposite direction of the link to carry several signals. The CMOS implementation supports integration into systems that already operate from 5 V rather than requiring the additional negative supply traditionally associated with RS-232.
Typical uses include industrial control links, point-of-sale equipment, test and measurement instruments, data-acquisition systems, and embedded equipment interfaces. In each case, the ADM239LAR can translate between a 5 V controller and an external RS-232 port. The 120 kB/s rate is suitable for moderate-speed serial links, while the integrated DC-DC converter simplifies implementation where only a positive 5 V rail is available.
The main design consideration is external line protection. Although the receiver input is specified to 30 V, exposed RS-232 ports may encounter larger transients or incorrect polarity. Appropriate surge and ESD protection should be added where the cable environment requires it, and unused driver outputs should be handled according to the manufacturer recommendations.
This page consolidates the verified ADM239LAR specifications, sourcing information, procurement details, interface-application guidance, and data gaps that are not resolved by the supplied manufacturer and distributor records.
Bộ thay thế dễ dàng lắp đặt cho ADM239LAR — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Không có bộ thay thế dễ dàng lắp đặt sẵn có cho sản phẩm này.
Yêu cầu các bộ thay thếADM239LAR Tỷ lệ tối đa & tính chất điện
| Product Type | 5 V powered CMOS RS-232 drivers and receivers |
| Điện áp cung cấp | 5 V |
| Driver Channels | 3 channels |
| Receiver Channels | 5 channels |
| Maximum Data Rate | 120 kB/s |
| RS-232 Output Swing | 9 V |
| Charge-Pump Capacitance | 1 μF |
| Receiver Input Voltage Rating | 30 V |
| Shutdown Feature | Low-power shutdown |
| Receiver State During Shutdown | Receivers active |
| Compliance | EIA-232-E and V.28 |
| Hộp | 24-lead SOIC |
| Package Width | 0.295 inch (7.50 mm) |
| Terminal Count | 24 terminals |
| Kiểu lắp đặt | Gull-wing surface mount |
| Temperature Grade | Industrial |
Hướng dẫn cấu hình chân ADM239LAR 0.295 inch (7.50 mm)
Cấu hình chân cho ADM239LAR (0.295 inch (7.50 mm) gói). Động cơ điện này có chân cổng, nguồn và đầu ra. Đối với các gói không phân極, tham khảo tài liệu thông số kỹ thuật của nhà sản xuất để biết hướng dẫn chính xác của chân 1 và chi tiết về vân footprint. Các ứng dụng phổ biến bao gồm thiết kế nguồn cung cấp điện, điều khiển động cơ và chuyển đổi tải.
Không có dữ liệu chân cụ thể sẵn có cho ADM239LAR.
Tham khảo: tài liệu kỹ thuật cho cấu hình chân đầy đủ.
Ứng dụng tiêu biểu
ADM239LAR phù hợp cho 6 Áp dụngs: Industrial Control Equipment, Test and Measurement Instrumentation, Point-of-Sale and Data Acquisition, Embedded Equipment Communication, Security and Access Systems, Medical and Diagnostic Equipment.
Industrial Control Equipment
The ADM239LAR suits industrial control equipment that must expose a multi-channel RS-232 port while operating from a 5 V control rail. Its 3 drivers support outgoing control or status signals, while 5 receivers provide more incoming channels than a compact two-direction interface typically offers. The 120 kB/s rate is suitable for supervisory links, configuration channels, and legacy machine controllers. The integrated DC-DC converter eliminates the need for a separate negative supply, while the 9 V output swing preserves RS-232 transition margin. Designers should still add cable-side surge protection because the verified 30 V receiver rating is not equivalent to unlimited transient immunity.
Được đề xuất
Test and Measurement Instrumentation
The ADM239LAR can serve legacy RS-232 control and measurement ports in laboratory instruments that already use 5 V CMOS logic. Three transmitter channels can carry commands, triggers, or service data, and five receiver channels can accept status and measurement acknowledgements. Its 120 kB/s maximum data rate is appropriate for instrument-control traffic that is not a continuous high-throughput data stream. The single 5 V supply arrangement simplifies isolation and power partitioning inside compact equipment, although engineers should check line capacitance, baud rate, and receiver thresholds against the actual cable.
Được đề xuất
Point-of-Sale and Data Acquisition
The ADM239LAR is appropriate for point-of-sale terminals, barcode equipment, and compact data-acquisition units that need more RS-232 channels than a minimal single-transceiver interface. Three outputs can support printer, scanner, or peripheral-control functions, while five inputs can monitor peripheral status. The integrated DC-DC converter and 1 μF charge-pump capacitors reduce the number of supporting power-supply components, and the 120 kB/s rate accommodates conventional transaction traffic. The 24-lead SOIC footprint should be reserved on a new design because verified drop-in alternatives in a smaller package cannot replace it directly.
Được đề xuất
Embedded Equipment Communication
The ADM239LAR can connect an embedded 5 V controller to an external RS-232 service port on industrial appliances and communication equipment. Using three drivers and five receivers allows the host to exchange multiple command, status, and diagnostic signals without three separate transceiver packages. Its 120 kB/s data rate is sufficient for configuration protocols, boot logs, and supervisory messages. The integrated DC-DC converter is valuable where the board lacks a negative voltage rail, and active receivers during shutdown can preserve incoming-status detection. Firmware and hardware should still define safe behavior for disconnected or shorted RS-232 lines.
Được đề xuất
Security and Access Systems
The ADM239LAR can support legacy RS-232 connections in access-control panels, alarm interfaces, and peripheral security equipment where a 5 V controller must communicate with external devices. The three transmitter channels can carry commands and acknowledgements, and five receiver channels can read sensors or status lines. The 120 kB/s rate is suitable for periodic supervisory traffic rather than high-bandwidth video transfer. Low-power shutdown is useful in duty-cycled equipment, while receiver operation during shutdown helps the controller detect incoming activity. Installation practice should include appropriate cable routing and line protection because external conductors may be exposed to surges.
Được đề xuất
Medical and Diagnostic Equipment
The ADM239LAR can support RS-232 service and legacy control ports in medical or diagnostic equipment that retains a 5 V logic supply. Its multiple channels provide flexible separation between commands, results, and status signals, while the 120 kB/s rate is suitable for instrument-control and service traffic. The single-supply DC-DC converter simplifies power conversion in systems where creating a negative RS-232 rail would add board area. Because the verified records do not confirm medical-specific qualification, this use should be treated as an electronic-interface function rather than evidence of regulatory approval. Appropriate isolation, leakage, and system-risk controls must be evaluated independently.
Được đề xuất
Dữ liệu tham khảo kỹ thuật cho ADM239LAR — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này |
|---|---|
| Package | 24-lead SOIC |
| Brand | Analog Devices |
| Product Type | RS-232 drivers and receivers |
| Supply Voltage | 5 V |
| Driver Channels | 3 channels |
| Receiver Channels | 5 channels |
| Maximum Data Rate | 120 kB/s |
| RS-232 Output Swing | 9 V |
| Receiver Input Voltage Rating | 30 V |
| Charge-Pump Capacitance | 1 μF |
| Shutdown | Low-power shutdown; receivers active |
Bảo phân biệt quan trọng
- Integrated single-supply DC-DC conversion (vsNo verified drop-in alternative)
- Asymmetric channel allocation (vsNo verified drop-in alternative)
- Receiver monitoring during shutdown (vsNo verified drop-in alternative)
Ghi chú thiết kế
Provide a stable 5 V supply and place the interface's supply decoupling close to the device power pins. The on-board DC-DC converter generates the RS-232 transmitter voltage, so the power rail must support both the CMOS logic load and charge-pump current. Follow the manufacturer datasheet for the exact input capacitor, voltage, and layout requirements before releasing the PCB.
Keep the 1 μF charge-pump capacitor connections and RS-232 driver outputs short, and route the receiver inputs away from switching nodes and high-current return paths. Maintain the differential geometry of connected RS-232 driver and receiver pairs. Because the supplied records do not contain the complete pin table, verify every connection against the manufacturer pin diagram before fabrication.
Do not treat the 30 V receiver input rating as unlimited transient protection. Add appropriately rated ESD or surge protection for cables that leave the enclosure, and confirm that protection capacitance will not degrade the intended 120 kB/s signaling. Also verify unused outputs and shutdown control states against the datasheet; generic RS-232 guidance may not match the ADM239LAR implementation.
Thông tin tuân thủ
The verified datasheet summary states that the ADM239LAR meets EIA-232-E and V.28 specifications. The supplied records do not explicitly confirm material-compliance or automotive-qualification status.
